The present invention relates to a container comprising a blank of material of limited flexibility, in particular cardboard, having wall portions in which at least one edge is separated from a bent-over edge strip portion by a bend line.
Containers of that kind can be used in many areas in daily life, either as round containers such as buckets, yoghurt pots or the like, or in polygonal form, such as for example a square or rectangular baking pan or mould.
For many purposes, it has also been found to be a practical proposition for the containers to be put on the market, in the condition of being folded to form flat articles for despatch or mailing. Particularly known in this connection are folded baking pans or moulds, which are enclosed with the ready-to-use baking mix. When required, a housewife unfolds the baking pan, fills it with the baking mix and puts it in the oven.
Known containers of that kind have edge strip portions which project in a collar-like configuration from the upper edge of the wall of the containers, and which are intended inter alia to stabilize the wall of the container. However, under practical conditions of use of such containers, it has been found that, in spite of the edge strip portions provided thereon, the wall portions of the container bulge outwardly or lose their shape. That is attributed to the fact that, for example in the case of foldable containers which are made from a blank, the edge strip portions are not properly folded over and then do not remain in the necessary angular position of about 90.degree. to the wall portions of the container, during use thereof. The tendency on the part of the edge strip portions, to return to their original position, is further promoted by the effect of heat for example in the case of a baking mould.